Question

identify the double displacement reactions among the following:

1. $kcl(aq) + agno_3(aq) \

ightarrow agcl(s) + kno_3(aq)$

1. $na_2so_4(aq) + bacl_2(aq) \

ightarrow baso_4(s) + 2nacl(aq)$

1. $h_2so_4(aq) + 2naoh(aq) \

ightarrow na_2so_4(aq) + 2h_2o(l)$
options:

• 1 and 2 only
• 1 and 3 only
• 2 and 3 only
• all of 1, 2, and 3
• none of 1, 2, and 3

Explanation:

Step1: Recall Double Displacement

A double displacement reaction involves the exchange of ions between two compounds, often forming a precipitate, gas, or water. The general form is \(AB + CD
ightarrow AD + CB\).

Step2: Analyze Reaction 1

For \(KCl(aq) + AgNO_3(aq)
ightarrow AgCl(s) + KNO_3(aq)\), \(K^+\) and \(Ag^+\) exchange with \(Cl^-\) and \(NO_3^-\). \(AgCl\) is a precipitate. This is a double displacement (precipitation) reaction.

Step3: Analyze Reaction 2

For \(Na_2SO_4(aq) + BaCl_2(aq)
ightarrow BaSO_4(s) + 2NaCl(aq)\), \(Na^+\) and \(Ba^{2+}\) exchange with \(SO_4^{2-}\) and \(Cl^-\). \(BaSO_4\) is a precipitate. This is a double displacement (precipitation) reaction.

Step4: Analyze Reaction 3

For \(H_2SO_4(aq) + 2NaOH(aq)
ightarrow Na_2SO_4(aq) + 2H_2O(l)\), \(H^+\) (from \(H_2SO_4\)) and \(Na^+\) (from \(NaOH\)) exchange with \(SO_4^{2-}\) and \(OH^-\). This forms water (a neutralization reaction, which is a type of double displacement where water is the product). So this is also a double displacement reaction.

Answer:

All of 1, 2, and 3